After the Tower suddenly appeared, individuals who wished to pursue their personal values began to inhabit it, coming to be called "hunters." Everyone had their own goals, but only a chosen few were acknowledged and given powerful skills by the mysterious structure. Kim Gong-Ja, a weak F-Class hunter without any skills, is envious of those who were blessed by the Tower. Letting his jealousy overcome him one day, Gong-Ja abruptly receives a S-Class skill that allows him to copy a skill from someone else—after they kill him.

Sooner than he likes, Gong-Ja gets to test his newly acquired ability on the legendary hunter known as the Flame Emperor. As he is dying, Gong-Ja learns the evil truth about the man he once admired the most. Receiving another potent skill that allows him to revive and go back in time by 24 hours, Gong-Ja devises a plan to travel 11 years into the past to eliminate the Flame Emperor and cement himself as the world's best hunter.